Differential actuator



Nov. 3, 1953 F. J. ROUAN ET AL DIFFERENTIAL ACTUATOR 2 Sheets-Sheet 1 Filed Nov. 3, 1950 llllllllgggilll & Illllllll ATTORNEY Nov. 3, 1953 ,F. J. ROUAN ET AL DIFFERENTIAL ACTUATOR 2 Sheets-Sheet 2 Filed Nov. 3, 1950 Patented Nov. 3, 1953 DIFFERENTIAL ACTUATOR Francis J. Rouan, Darien, Conn, Walter J. Hanson, Port Chester, N. Y., and Alva G. Russell, Stamford, Conn, assignors to Pitney-Bowes, Inc.-, Stamford, Conn., a corporation of Delaware Application November 3, 1950, Serial N 0. 193,814

5 Claims. 1

This invention relates to a differential actuator for use in actuating numeral wheels of registering mechanism in accordance with a selected value.

The differential actuator is particularly adapted for use in a postage printing and metering device, wherein values set for printing are accumulated and registered in numeral register Wheels during a printing cycle of operation.

The device herein disclosed is an improvement over an actuator disclosed in Patent No. 2,534,2'7 6.

Normally in postage meter operation, with present commercial machines, a printing cycle is effected in approximately one-fourth of a second, and actuation of a register numeral wheel is effected in about one-fourth of the printing cycle of operation. Therefore, the actuation of the nu meral register wheel is completed in about onesixteenth of a second.

In the device of this invention, advantage is taken of the full 360 printing cycle of operation to perform the actuation of the numeral register wheels. This results in improved operation of the registering mechanism.

It is one object of the invention therefore, to provide an improved differential actuator wherein the drive of the register numeral wheels is effected at the beginning of a cycle of operation and continues throughout the cycle.

It is another object of the invention to provide an improved differential actuator wherein one element of the actuator is non-"rotative and contains variable but fixed numbers of teeth, and another element which is rotative, contains a fixed number of teeth, and to effect the drive of the rotative element through adjustable pinion means, a distance proportionate to the differences in the numbers of teeth of the two elements.

It is another object to provide a differential actuator wherein one element thereof, which is stationary, contains variable numbers of teeth, and wherein another element thereof, which is rotatable, contains a fixed number of teeth, and to effect a resultant drive therefrom of a re'gi's ter numeral wheel in accordance with a difference in the numbers of teeth of the rotatable element relative to a selected number of teeth of the stationary element.

A preferred embodiment of the invention is Fig. 2 is a vertical sectional view taken substantially along the line 2-2 of Fig. 1, with parts shown in elevation;

Fig. 3 is a sectional plan view through the actuator mechanism and is taken along the line 3-3 of Fig. 1;

Fig. 4 is a view looking in the direction of the arrow 4 on Fig. 3, showing a pinion shifting element;

Fig. 5 is a sectional View taken along the line 5-5 of Fig. 1;

Fig. 6 is a sectional view through the main shaft along a line indicated by the arrow 6 of Fig. 1, showing a setting lever locking element and its relation to a recess in the shaft when the shaft is in a home position; and

Fig. '7 is a detail perspective showing a modified toothed arrangement of the actuator drive.

Referring to the drawings in detail, the differential actuator, generally indicated at A, is shown in operating position within a postage meter casing Ii). Also mounted within the casing in is a main shaft II, which shaft is supported in end bearings l2 and It and is adapted to be coupled to 'a drive, as indicated at I4. Said shaft ll also carries a printing cylinder as indicated at NC.

Numeral register wheels 15 are mounted on shafts [5-48, which shafts are suitably supported within the casing [0, each wheel having a gear ll forming a part thereof. Each numeral wheel 15 is also adapted. to be independently driven through suitable differential means, such as i1lustrated in a co-pending application Serial No. 760,590, now Patent No. 2,612,104 and transfer to a wheel of next higher order is effected through a Geneva transfer pinion I8. Each shaft l6 supports a separate group of numeral wheels to provide two independent register units. t will only be necessary however, to consider the actuation of a single numeral wheel for an understanding of the invention.

Transmission gearing is provided between an actuator driven or crown gear 22 and the numerai wheel gear H, which gearing includes an intermediate goal: it and a gear 25. The crown gear 22 forms an integral part with the transmission gear 2! and is freely mounted on a bearing 23, which bearing forms a part of a support '24.

The support 25- is fixed to an actuator shaft 25, which shaft is positioned transversely to the main shaft H and is supported within bearings 26-26 carried by the side walls Ma -Sim of the casing I9. Through a spiral gear drive, generally indicated at 21, Fig. 2, the actuator shaft 25 is rotated one revolution for each printing cycle of the machine Or driving cycle of the main shaft II. For the sake of simplification of the drawings, such mechanism as one revolution clutch controls and the like, for limiting each cycle of operation to one revolution, are not shown, but mechanism for such purposes may be found in Patent No. 2,141,119.

The support '24. has a radial extension or arm 28, which arm has an opening 29 therethrough, and is adapted to support the ends of a small splined shaft 3i within bearings 32-32a.

A pinion 33, fixed to one end of the splined shaft 3|, meshes with the crown gear 22 and is adapted to receive planetary movement therearound when the actuator shaft 25 is rotated, which rotation moves the support "it in a circular path. Another pinion 34, having a hub portion 34a with an axial splined opening therein, is axially slidable on the splined shaft iii.

A gear 35, which will be known as the actuator gear, is associated with the slidable pinion 34, and preferably comprises a plate having circular concentric rows of rectangular shaped apertures 3'; therein. Normally, only ten rows of apertures are required to serve all values from through 9 but eleven rows are disclosed in the drawing to permit actuation of a $1.00 value in a meter unit having two setting levers, which otherwise would be limited to a 99 value. The tens setting lever would be advanced one unit further than the normal 0 through 9 positions or to the position. A similar condition would apply to provide a $10.00 value with three setting levers or a $100.00 value with four setting levers, if desired.

The actuator gear 35 is rigidly supported in a vertical position on a plate 36, the plate being rigidly supported on tie-rods 4B. As shown in Fig. 2, the tie-rods are carried by one wall Hid of the frame It and by a bracket 4?. Spacer sleeves 48 are provided between each of several plates 36 of a plurality of actuator units. The plate 33 and gear 35 are secured to each other by means of pins 36a, which pins also support a retainer ring 50. As best shown in Fig. 3, said retainer ring is provided for the purpose of maintaining the bearing end 32 of the support 24 in engagement therewith, to thereby support the shaft 3| and pinion 34 in a correct drive relation with the gear The apertures 3'! in the actuator gear 35 provide spaces for the teeth of the pinion 34 to enter during a cycle of operation, and the portions 31a, between each of said apertures 31, will perform in the manner of gear teeth in effecting the drive of the pinion 34 during the planetary motion of the pinion around a selected circular row of apertures and gear teeth Ell-4111 respectively. It will be understood that projecting teeth 3719 may be substituted for the aperture arrangement as shown in Fig. '7, if desired.

Two radial slots it-39 are provided in the gear plate 35, at the home position of the pinion supporting member 24, as best shown in Figs. 3 and 5, to permit two of the innermost teeth of the pinion 34 to slide radially when effecting ad- ,iustment of said pinion relative to a selected group of actuator teeth 31a. The slots 39-39 are spaced. the same as the apertures 31 to thereby permit rotation of the pinion 34 as soon as the printing cycle of operation is started. By means of said slots rotation of the pinion 34 is prevented while the pinion supporting number 24 is in the home position.

Adjustment of the pinion 34 is effected by means of a setting lever 4|, pivotally mounted on a shaft 42, which setting lever has one end of a link 43 secured thereto at 44. The opposite end of the link 43 is forked as at 45, Fig. 4, whereby it is adapted to straddle a reduced end 46 projecting from the support 24 to guide the link 43 during a pinion setting operation. Contact between the link 43 and the adjustable pinion 34 is provided by means of two pins 49-49, projecting from the inner surface of the link 43, which pins engage both faces of the pinion 34 in the manner best shown in Fig. 3. When, therefore, the setting lever 4| is rocked about the shaft 42, the pinion 34 is moved and aligned with a selected row of apertures and teeth 31 and 31a respectively. By means of a spring urged detent pawl 5|, and its association with a toothed segment portion 5|a of the setting lever 4|, the setting lever 4| is adapted to be retained in any selected value position.

The first or innermost row of teeth 31a has teeth equal in number to the number of teeth of the crown gear 22, and when the pinion 34 is aligned with said teeth, both pinions 34 and 33 will rotate around the teeth of the gear 35 and crown gear 22 respectively without effecting rotation of the crown gear. This agrees with the 0 setting of the setting lever 4|.

The second row of teeth 3111 contains four more teeth than the crown gear 22, and, during a cycle of operation, will effect rotation of the crown gear 22 in accordance with said tooth differential, a distance sufficient to cause the numeral register wheel |5 to rotate one digit. In a like manner each succeeding row of teeth 31a is increased by four teeth to effect a proportionate increase of rotation of the crown gear 22 accordingly during a cycle of operation.

Rotation of the crown gear 22 will begin as soon as the pinion 34 begins to rotate around the teeth 31a, owing to the proportionate increase in the distance of travel of the pinion 34 relative to that of the pinion 33, the latter being positioned at a shorter radius from the axis of the shaft 25. Continuous rotation of the crown gear 22, during the full operating cycle, provides for easy register wheel operation.

Locking of the setting lever 4| is provided immediately upon starting a cycle of operation by obstructing movement of the detent pawl 5|. To accomplish the latter, a tail piece 52 of the detent pawl 5| normally engages with a hooked end of a lever 53, which lever rocks with a companion lever 54, both levers being pinned to a shaft 55. The upper end of the lever 54 will move freely within a slot 56 in the main shaft II when the shaft is in a home position but will be blocked against movement when the peripheral surface of the shaft moves into the path of the end of the lever 54.

Having described the claimed is:

1. In a device for actuating a register wheel in accordance with a selected set value and comprising, a stationary gear having circular rows of varying numbers of teeth concentrically grouped relative to the face thereof, and a rotatable crown gear concentrically positioned within the innermost row of teeth, a shaft having a settable pinion rotative therewith and longitudinally adjustable thereon relative to a selected row of teeth of the stationary gear, transmission gearing meshing with a register wheel and driven by the crown gear, a pinion meshing with the crown gear invention, What is n.) and fixed to said shaft, and means to move the shaft through a plane normal to its own axis of rotation, whereby the settable pinion will be moved around the teeth of the stationary gear, and whereby the crown gear will be driven by the pinion meshed therewith in accordance with the difference in the numbers of teeth of the crown gear and selected row of teeth of the actuator gear.

2. A differential actuator comprising a nonrotative gear having concentric circular rows of teeth wherein the total number of teeth of each row differ, a rotative gear having one circular row of teeth, a pinion assembly including a shaft having one pinion longitudinally adjustable thereon but in driving relation therewith and having a second pinion fixed thereon, said adjustable pinion being adapted for engagement with a selected group of teeth of the non-rotative gear, said second pinion meshing with the teeth of the rotative gear, and means to move the shaft through a plane normal to its own axis of rotation, whereby rotation of the adjustable pinion is effected around the selected row of teeth of the non-rotative gear, and the second pinion is rotated accordingly to effect the drive of the rotative gear a distance determined by the difference in the selected number of teeth of the non-rotative gear and the number of teeth of the rotative gear.

3. A differetial actuator comprising a non-rotative gear having concentric circular rows of teeth wherein the total number of teeth of each row differ, a rotative gear having a circular row of teeth positioned concentric with the innermost teeth of the non-rotative gear, a pinion assembly including a shaft having one pinion longitudinally adjustable thereon but in driving relation therewith and having a second pinion fixed thereon, said adjustable pinion being adapted for engagement with a selected group of teeth of the non-rotative gear, said second pinion meshing with the teeth of the rotative gear, and means to move the shaft through a plane normal to its own axis of rotation, whereby rotation of the adjustable pinion is effected around the selected row of teeth of the non-rotative gear, and the second pinion is rotated accordingly to effect the drive of the rotative gear a distance determined by the difference in the selected number of teeth of the non-rotative gear and the number of teeth of the rotative gear.

4. A differential actuator comprising a fixed plate having concentric circular rows of apertures wherein the total number of apertures of each row differ, a rotative crown gear having one circular row of teeth positioned concentric with the innermost circular row of apertures oi the non-rotative gear, a pinion assembly including a shaft having one pinion longitudinally adjustable thereon but in driving relation therewith and having a second pinion fixed thereon, said adjustable pinion being adapted for engagement with a selected row of apertures in the fixed plate, said second pinion meshing with the teeth of the rotative gear, and means to move the shaft through a plane normal to its own axis of rotation, whereby rotation of the adjustable pinion is effected as the teeth of the pinion pass from aperture to aperture around the selected row of apertures, and the second pinion is rotated accordingly to effect the drive of the rotative gear a distance determined by the difference in the selected number of apertures and the number of teeth of the rotative gears.

5. A differential actuator comprising a fixed plate having concentric circular rows of apertures wherein the total number of apertures of each row differ, said fixed plate also having two radial slots therein at the home position spaced in the same proportion as the spacing between apertures, a rotative crown gear having one circular row of teeth positioned concentric with the innermost circular row of apertures of the nonrotative gear, a pinion assembly including a shaft having one pinion longitudinally adjustable thereon but in driving relation therewith and having a second pinion fixed thereon, said adjustable pinion having two teeth engaging the radial slots when adjustment is eifected to align the pinion with a selected group of apertures, said second pinion meshing with the teeth of the rotative gear, and means to move the shaft through a plane normal to its own axis of rotation, whereby rotation of the adjustable pinion is effected as the teeth of the pinion pass from aperture to aperture around the selected row of apertures, and the second pinion is rotated accordingly to effect the drive of the rotative gear a distance determined by the difference in the selected row of apertures and the number of teeth of the rotative gear.

FRANCIS J. ROUAN. WALTER J. HANSON. ALVA G. RUSSELL.

References Cited in the file of this patent UNITED STATES PATENTS Number 

